This invention is directed to a zero insertion force (ZIF) card connector in which a flexible film having electrical circuitry thereon is disposed therein for receiving a printed circuit board (PCB) card.
The use of flexible film i.e., printed circuitry on this insulating material such as polyester film, to interconnect one circuitry to another whereby to provide a means to achieve extremely high density interconnections is known in the art. Further, flexible film circuitry provides impedance matching and thus transmission line characteristics. connectors using such film are known from several patents dating back to the early 1960's. U.S. Pat. No. 3,102,767 is one such disclosure. Subsequently issued patents include U.S. Pat. No. 3,609,463 wherein a spring biased push member is utilized to urge the contacts on a flexible material against an inserted card. In this and other disclosures, e.g., U.S. Pat. No. 3,401,369, the card is inserted against the biased film, i.e., an insertion force is required. During insertion, the circuit pads on the film and card rub or wipe against each other to clean away debris and the like.
Zero insertion force card edge connectors are known from U.S. Pat. Nos. 3,614,707 and 3,922,054. Cards are inserted without force by spreading apart the side walls defining the slot. Spring members, being either separate components or forming an integral part of the connector, e.g., as shown in U.S. Pat. No. 3,922,054, provide a biasing force to urge the film against the card when the connector is closed.
U.S. Pat. No. 4,629,270 represents a later approach to provide a ZIP connector. The connector thereof comprises a base member for mounting on a circuit with a card receiving space therealongside, actuator means with cams thereon slidably mounted for longitudinal travel on the base member, and a module having one surface for receiving a free side of a flexible film. Additionally, there is one or more cam followers, with the module being mounted so that the one surface faces the card receiving space and the one or more cam followers cooperate with the cams so that by moving the actuator means longitudinally, the module moves laterally towards and away from the card receiving space and further perpendicularly relative to the base member.